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bubbabooga

By bubbabooga,
in Engines & Forced Induction

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bubbabooga Rising Star

bubbabooga

Posted
Posted

what cam gear settings would you recomened to run using rb20det exhaust cam in r32 rb25de head??

inlet cams seem to be identical

but if changing exhaust cam is as easy as swapping them over and dialling them in with adjustable cam gear then why not..

have both silvertop rb20det and r32 rb25de heads sitting next to each other..

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kozmoz Newbie

kozmoz

Posted
Posted

Hey guys, im currently building a RB30/25 DET, will be turbo'n it after ive done the internals, atm ive stripped the block down and have had the cylinders honed, what would you suggest i do to the crank, rods, pistons, etc. want it to be able to handle 14psi ish. if not more depending on what has to be done.

Cheers, Sam

Cubes Grand Master

Cubes

Posted
Posted
what cam gear settings would you recomened to run using rb20det exhaust cam in r32 rb25de head??

inlet cams seem to be identical

but if changing exhaust cam is as easy as swapping them over and dialling them in with adjustable cam gear then why not..

have both silvertop rb20det and r32 rb25de heads sitting next to each other..

As I mentioned in previous post. The Rb20det cam has the same duration and lift as the rb25de but the centerline is more suitable for N/A. However the rb25de cam appears to do fairly well with the 3ltr.

If you drop the rb20det cam in to the rb25de head you will drop power compared to the rb25de smaller cam as the centerline of the rb20det cam is not suited to the rb30det.

So.. Drop a set of adj. cams gears on to it.

But honestly.. I wouldn't bother. The rb25de cams appear to do fairly well. Wait until you throw a set of cams at it then bother.

kozmoz Newbie

kozmoz

Posted
Posted
14psi doesn't mean much..

What turbo? what power goal?

I was thinking of a bit power for more top end, so a bigish turbo (dont know specifics of it yet) as for its going to be daily driven so nothing crazy =p. power goal prolly round the 300-400whp or upwards, dont wana spend to much on internals, first time working on one of these motors. not sure of its potential. just want some ideas of what to do.

Cheers, sam

Cubes Grand Master

Cubes

Posted
Posted

Not really suitable for this thread but typically if your sticking with the std exh. manifold don't go any bigger than a gt3076r .82.

If your going to go an aftermarket exh manifold GT35r or larger. :)

Stock internals handle quite a bit of power (400-500rwhp) Its rev's/missed shifts that kills them.

fr0st Experienced

fr0st

Posted
Posted

I have a generic engine building question, probably easy an one for you guys but it's my first engine build so I'm trying to get my research done.

I've got a standard 30 block, crank and rods, all are in good condition and don't require grinding. I also have a full set of standard size ACL race bearings.

Questions is, if I simply put them in and torque to spec the clearances will most likely be all over the place and no good?

And, if the clearances aren't right do I have to get the crank ground to match the bearings?

I'm more than likely just going to hand the bottom end components to an engine builder and have them do it, I'd just like to know the process.

Cheers all

bubba Grand Master

bubba

Posted
Posted

Get the crank ground for oversize bearings just to be on the safe side..

I didn't to start with and turned out the crank had some massive end-float and it munched out my thrust washers and nearly ended in big tears.

For the $120 to get the crank machined and the ~$80 for .010 oversize bearings, I should have done it to begin with and I wouldn't have had to pull the motor out again!

Cubes Grand Master

Cubes

Posted
Posted

Bubba...

As the crank is nitreded from factory its best not to grind the crank if possible.

If the motor had massive end-float its the assembler that didn't do his job ensuring everything was in spec when the motor was pulled down.

I went with King bearings bimetals which use an oversized thrust so a better alternative than machining the crank completely with oversized bearings.

So far so good 90,000km's and counting. :D

bubba Grand Master

bubba

Posted
Posted (edited)

It's because we just slapped it together with standard spec bearings. Had it reground, fresh bearings (I run NDC with no dramas, japs ftw), new oil pump and have done another 10,000 odd (hard) km with no dramas :D

Edited by bubba
xsv_32 Enthusiast

xsv_32

Posted
Posted

Hi all, im about to put the head onto my 30 and i need to sort all of the bottom end stuff before i end up having to squeeze past manifolds to do so. Anywho, Im running a front mounted oil cooler which looks like the pic below at the block end. Now, the sandwhich plate provides an easy and simple way to tap into your oil flow to run gauges, so what do i do with the factory sensor? Can i block it with a bolt? Im not fussed if the factory oil gauge in the cluster doesnt go but without it will my oil light stay on? And last but not least, where does the factory sensor thread into the block?

Any advice would be mint.

Cheers

bubba Grand Master

bubba

Posted
Posted

Factory sensor threads into the block on the same side as the oil filter but further towards the back of the engine. I put a T here and ran the sender for my aftermarket gauge off the same spot with the stock sender still installed.

xsv_32 Enthusiast

xsv_32

Posted
Posted
Factory sensor threads into the block on the same side as the oil filter but further towards the back of the engine. I put a T here and ran the sender for my aftermarket gauge off the same spot with the stock sender still installed.

Awesome , cheers for that. I think il run th factory gauge and then just the gauges off the sandwich plate. Using a N1 pump anyone know what sort of oil pressure i should be running?

daisu Mentor

daisu

Posted
Posted

I intend on reassembling the engine myself, but I don't want to buy standard size bearings then assemble it and find the tolerances are out.

Will the engine machinists be able to tell me whether I'll need standard or oversize bearings when I get the crank linished?

bubba Grand Master

bubba

Posted
Posted
Awesome , cheers for that. I think il run th factory gauge and then just the gauges off the sandwich plate. Using a N1 pump anyone know what sort of oil pressure i should be running?

I'm running an N1 pump and I see 100psi on cold start (I also belief the relief spring is 100psi), at normal operating temp I see 10-20psi at idle depending on oil temp. 40psi ~2000rpm, 60psi ~3000rpm, 80psi ~4000rpm and from about 5000rpm onwards it's hitting 100psi.

Adriano Grand Master

Adriano

Posted
Posted
I intend on reassembling the engine myself, but I don't want to buy standard size bearings then assemble it and find the tolerances are out.

Will the engine machinists be able to tell me whether I'll need standard or oversize bearings when I get the crank linished?

Machininst will be able to measure it and tell you if it needs to be ground.

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